Rotary sharpeners



29, 19677 M. GREENFOGEL 3,337,998

ROTARY SHARPENERS Filed Dec. 24, 1964 V 2 Sheets-Sheet l INVENTOR MAURICE GREENFOGEL PPM J ATTORNEYS. v

A g 2 1967 v M. GREENFOGEL ROTARY SHARPENERS Filed Dec. 24, 1964 2 Sheets-Sheet 2 INVENTOR WHV/Q/KZ G/PZZ/VFOGKL United States Patent Ofliice 3,337,998 Patented Aug. 29, 1967 ABSTRACT OF THE DISCLOSURE Sharpener for a knife blade edge. Includes a pair of complementary substantially circular sharpeners having overlapping peripheral portions to receive therebetween the blade edge. Sharpener includes an arbor adapted to be mounted on its rotary support; a pair of complementary members connected to the arbor, one of the members being fixed to the arbor and the other being connected to the arbor in floating relationship to the fixed member; means such as a spring for resiliently biasing the members for movement away from one another; the members each having a laterally extending flange defining a substantially true circular portion; and an endless abrasive band circumscribing the complementary flange portions of the members to define a true circular abrading surface for engaging a cutting edge during the sharpening operation. The resilient means maintains the members biased against the inner circumference of the endless band to detachably secure it to the members by friction.

This invention relates in general to rotary sharpeners, and more specifically to rotary sharpeners adapted for use on cloth cutting'machines utilizing a reciprocating knife.

Cloth cutting machines generally include a standard on which a cutting knife is reciprocally mounted. Such cutting machines are generally utilized in the garment industries for cutting through stacks of cloth sheets in accordance with a given pattern. Consequently, to maintain the edge of such a cutter sharp at all times it is customary to provide such machines with sharpeners adapted to engage with the cutting edge of the knife blade to renew the cutting'edge thereof.

Heretofore, as evidenced by US. Patent 2,624,162, such sharpeners comprised a pair of companion rounded or circular grindstones disposed in overlapping relationship. It has been observed that in use such grinding stones tend to get out of round due to uneven wear. Thus, when such stones lose their roundness, the efliciency thereof decreases accordingly.

It is therefore an object of this invention to provide such cutters with improved rotary sharpening means which are constructed and arranged so as to maintain the respective roundness thereof throughout their entire operating life.

It is another object of this invention to provide an improved rotary sharpening means in which the abrasion means thereof can be readily maintained and/or replaced with a maximum of ease and in a minimum of time.

Still another object of this invention is to provide an improved sharpening means in which the abrading surface of the sharpener comprises an endless band supported upon complementary members constructed and arranged so as to insure the maintenance of the true roundness of the band so as to attain maximum efiiciency.

In accordance with this invention the foregoing objects and other features and advantages are attained by a rotary sharpener comprising a pair of complementary counterrotating sharpeners having portions thereof disposed in overlapping relationship. Each of the respective rotary New York, N.Y., a corv sharpeners are substantially similar in construction and each comprises an arbor means adapted to be mounted on a rotating support sleeve. A pair of complementary shoe members are connected to the arbor means of each rotary sharpener. The arrangement is such that one of the complementary shoe members is fixedly secured to its respective arbor means whereas the other shoe member is connected in floating relationship thereto so as to be rendered movable relative to the complementary fixed shoe member. Means in the form of a resilient spring is interposed between the adjacent ends of the respective complementary shoe members for exerting a bias therebetween.

In accordance with this invention, each of the respective shoe members has a circumscribing surface defined as a segment of a circle in which the respective circular segments have a total angular degree of slightly less than 360. For example, the circular segment of one shoe member may define a true half circle of 180 whereas the other shoe member is provided with a circular segment which is slightly less than a true half circle or 180, e.g. or the like. The arrangement is such that the resilient spring disposed between the adjacent ends of the respective shoe members exerts a force or bias tending to move the floating shoe member away from the fixedly secured shoe member.

Means in the form of an endless circular band of abrading material is arranged so as to circumscribe the total peripheral circular segments of the respective shoe members. Accordingly, the band is retained in position due to friction resulting from the biasing of the floating member relative to the fixedly secured member and the band of abrasive defines a substantially true circular or rounded grinding surface that is maintained throughout the wear thereof.

The respective rotary sharpeners are substantially similar in construction, but can differ in the number of endless bands of abrasive material carried thereon.

A feature of this invention resides in the provision of an improved sharpener which comprises a pair of relatively moveable shoe elements constructed and arranged for supporting thereon an endless band of abrasive material which can be readily removed and/or replaced as may be required.

Another feature of this invention resides in a rotary sharpener construction in which the roundness of the abrasive material thereof is insured throughout the operating life thereof.

Another feature of this invention resides in the provision wherein the abrasive portion of the sharpener can be readily removed and replaced with a minimum of effort and at a minimum of expense.

Another feature of this invention resides in the provision wherein the respective sharpening mechanism is relatively simple in construction, can be readily fabricated and is positive in operation.

Other features and advantages will become more readily apparent when considered in view of the drawings and description thereof in which:

FIG. 1 illustrates an elevation view of the improved sharpening means of the instant construction as adapted for use with a straight knife cloth cutting machine.

FIG. 2 is a plan view of the sharpening means as illustrated in FIG. 1.

FIG. 3 is a bottom plan view of FIG. 1.

FIG. 4 is a sectional plan view taken along line 44 of FIG. 1.

FIG. 5 is a sectional of FIG. 1.

FIG. 6 is a vertical cross-sectional view of one of the rotary sharpeners taken along line 66 of FIG. 2.

plan view taken along line 5-5 FIG. 7 is a sectional view taken in elevation of the other rotary sharpener taken along line 77 of FIG. 2.

FIG. 8 illustrates an endless abrasive band shown in perspective.

FIG. 9 illustrates a method by which the endless band of FIG. 8 may be formed.

FIG. 10 is a perspective view of a cloth cutting machine as disclosed in US. Patent 2,624,162 on which the improved sharpening means of the instant construction may be employed.

Referring to the drawings, there are shown therein improved rotary sharpeners of the instant invention which are adapted to be utilized in combination with straight knife cutting cloth machines, e.g. of the type disclosed by Patent No. 2,624,162. As is well known to those skilled in the art, such cloth cutting machines comprise essentially a standard for supporting a motor means which is operatively connected to a reciprocating straight cutting knife. Such cutting mechanics are commonly employed in the garment industry wherein stacks of cloth material are cut to shape by moving the cutting machine through the stack in accordance with a predetermined pattern.

In order to maintain the cutting edge of the straight knife of such machines at its optimum sharpness, rotary grinding or sharpening means 20 is provided to engage the cutting edge of the knife.

In accordance with this invention, the improved rotary sharpening means 20 comprise a pair of complementary sharpeners 22, 24 which are rotatably disposed on shafts 26, 28 respectively. Sharpeners 22 and 24 are rotated in opposite directions. Each of the respective counter-rotating sharpeners 22, 24 is substantially similar in construction except as will be hereinafter note-d.

As best seen in FIGS. 1, 2 and 3, the sharpener means 20 comprises a pair of complementary rotary sharpeners 22, 24 which are constructed and arranged so as to have portions thereof disposed in overlapping relationship. Each of the respective sharpeners 22, 24 comprises an inner support sleeve which is adapted to receive and rotate on the shaft 26 or 28. As shown in FIGS. 6 and 7, each of the respective inner sleeves 30 is provided with a laterally extending flange portion 32 disposed adjacent one end thereof. Also, the respective ends of the inner sleeve 30 are provided with externally threaded portions 30A, 30B. An arbor 34 formed with a mounting flange 36 is assembled on the extended end of the sleeve 30. AS shown, the arbor 34 has one end thereof disposed adjacent a flange 32 of the sleeve- 30. If desired, a suitable fiber washer 38'may be interposed between the flange end of the arbor 34 and the flange 32 of the sleeve 30. The arbor 34 is secured in position on the extended end of the sleeve 30 by means of a nut 40 which is threaded to the threaded end of the sleeve 30, a fiber washer 42 being disposed between the end of the arbor 34 and the nut 40. Threaded or suitably connected to the other end of the sleeve 30 is a spur gear, 44 disposed in meshing relationship with a drive gear 46 (FIG. 1) which is driven by the motor of the machine (not shown), to thereby drive (rotate) the sharpeners 22, 24 about the fixed shafts 26, 28.

In accordance with this invention, a pair of complementary shoe members 48, 50 or 52, 54 are connected to the arbor 34 of the respective sharpeners 22, 24. Each of the respective complementary shoe members 48, 50; 52, 54 is provided with a body portion and a laterally extending flange portion 48A, 50A; 52A, 54A. The arrangement is such that the peripheral surface of the respective flange portions defines a segment of a circle. In accordance with this invention the total segmental portions circumscribe slightly less than 360 angular degrees. In the illustrated embodiment the peripheral flange portion e.g. 48A or 52A of one of the shoe elements 48, 52 defines a segment of a true half circle or 180". The segmental flange portion 50A, 54A of the other complementary shoe members 50, 54 define a segment of a circle which is slightly less than that of a true half circle, or approximately 175.

However, as an alternate construction, each of the respective circumferential segmental portions of the respective shoe members 48, 50 or 52, 54 may define segments of a circle which are each slightly less than a true half circle, e.g. 177. Accordingly, the overall consideration is that the total angular degrees of the respective complemental shoe elements should be less than 360 so that one shoe element is free to float relative to the other as will be herein described.

One of the shoe elements 48 or 54 is fixedly secured to the mounting flange 36 of the arbor 34. As best seen in FIGS. 1 to 7, the fixedly secured shoe segment 48 or 54 is connected to the flange of the arbor by means of screw fasteners 58 threaded into tapped holes. The other shoe segment 50 or 52 is mounted on the flange of the respective arbor 34 so as to be disposed in floating relationship with respect thereto.

In accordance with this invention, the flange 36 of the arbor 34 is provided with an aperture through which a pin 60 is extended. The floating shoe member 50 or 52 is also provided with a pair of apertures 62 which are adapted to be disposed in alignment with the pin 60 extending through the flange 36 of the arbor so as to receive the same. However, in accordance with this invention, and as best seen in FIGS. 2 and 3, the apertures of the floating shoe member 50, 52 have a diameter which is greater than that of the diameter of the pin 60 extending through the flange 36 of the arbor 34. Accordingly, the shoe members S0, 52 are secured to their respective arbors 34 by means of pins 60 and because the diameter of the pin holes 62 in the shoe members are larger than the diameter of the pin 60, the shoe members are free to float relative to the arbor and the fixedly secured shoe member 48 54 thereto. 7

As will be noted in FIG. 7, both the floating shoe member 50 or 52 and its complementary member 48 or 54 is provided with an internal groove 48B, 50B, 52B, 543 which is adapted to receive the flange 36 of the arbor 34.

To bias the respective shoe members 48, 50 and 52, 54 away from each other, a spring means 64, 65 is interposed between the adjacent end portions of the respective shoe members 48, 50 and 52, 54. As best seen in FIGS. 4 and 5, the adjacent end portions of the respective shoe members are provided with a bore 68 or 70 which is adapted to receive a compression coil spring 64 or 65, respectively. The arrangement is such that the springs 64 or 65 tend to bias the floating member 50 or 52 away from the fixedly secured shoe member 48, 54, the pins 60 resisting the force of the spring 64 or 65acting on the float member 50 or 52. Thus as is readily apparent 'm FIGS. 2 and 3, the moveable member 50 or 52 is mounted on the arbor 36 for limited relative movement with respect to the fixedly secured show member 48 or 54.

In accordance with this invention, an endless band 72 formed of an abrasive material is arranged to circumscribe the extending flange portions of the respective rotary sharpeners 22, 24. The endless band 72 of abrasive material is formed so as to define a true circle. Therefore, the arangement is such that upon compression of the spring 64 or 65 to shift the floating shoe member 50 or 52 toward the respective fixed member 48 or 54, the circumference of the respective flanges of the complementary shoe members is made less than that of the circular band 72. Consequently, the circular band 72 can be readily positioned about the combined laterally extending flanges of the respective shoe members 48, 50' or 52, 54. Upon the release of the pressure on the spring 64 or 65 the floating shoe member is again biased outwardly against the interior circumference of the endless band, and thereby insures a positive frictional engagement of the endless band 72 to the respective peripheral edge portions of the respective shoe members 48, 50 or 52,54. In this manner it will be readily noted that the endless band 72 can be readily removed and/ or replaced from the respective shoe members of the sharpening means with a minimum of effort. As best seen in FIGS. 6 and 7, the respective sharpeners are identical in structure with the exception that the shoe members 48, 50 of one sharpener 22 is constructed with a pair of spaced apart laterally extending flanges 48A to define an annular groove 74 disposed therebetween. The other sharpener is formed with shoe members for accommodating but one band. The arrangement is such that in operation the abrasive band 72 of the sharpener 24 is disposed in overlapping relationship with the pair of abrasive bands 70 formed on the other complementary sharpener 22, as best seen in FIG. 1. Thus, the complementary abrading bands 70 of the respective sharpeners 22, 24 are disposed in overlapping relationship so that a knife edge 76 disposed therebetween is subjected to a sharpening operation.

With the instant invention it will be noted that the construction and arrangement of the respective sharpeners 22, 24 is such that the endless abrasive band 72 disposed therearound is maintained at all times throughout the entire life ther'eof in a truly round or circular relationship for optimum sharpening efficiency. The true circularity of the endless bands 70 of abrasive material is thus achieved by the expedient employed in making the respective shoe members of the companion sharpeners 22, 24 with a circumfe-rence forming segmental portions totaling slightly less than 360. This slight angular deviation from a true circle provides a means'whereby the respective shoe members 48, 50 or 52, 54 can be rendered relatively moveable with respect to each other so as to enhance the removal and replacement of the endless bands 70 thereon, also the respective shoe elements of each sharpener complement one another to maintain the true circularity of the abrasive bands. In accordance with the instant invention, optimum grinding efficiency can thus be maintained at all times, since the roundness of the abrading surfaces are constantly maintained for the life of the abrading material.

FIG. 9 illustrates a method whereby the endless bands 72 of abrading material of FIG. 9 may be made. As shown, a strip of backing material 80 is helically wound with the convolutions thereof disposed in abutting relationship about a forming mandril 82. A layer or strip 84 of abrasive material is helically wound with the convolutions thereof likewise disposed in abutting relationship in the opposite direction on the layer 80 of wound backing material. A suitable adhesive or cement is utilized in adhering the helically wound strip of abrasive material 84 on the helically wound backing material 80. With the respective strips of backing material 80 and abrasive material 84 secured to one another, the mandril 82 is removed. The cylindrical formation of the backing material 80 and abrasive 84 thus formed is then severed into relatively narrow strips or bands 72 which are sized as may be required to define the endless band, as illustrated in FIG. 9, and which are utilized in conjunction with the rotary sharpeners 22, 24 hereinabove described. By the method described, the endless bands 72 of abrasive material can be readily formed with a minimum of effort and at a minimum of expense.

FIG. 10 illustrates a typical cloth cutting machine, such as that shown in US. Patent 2,624,162, on which the sharpening device of the present invention may be employed. This machine comprises a blade 115 mounted to reciprocate in a post or standard 116 and driven by a motor 117. The sharpener of the present invention may be mounted on the cloth cutting machine, as on carriage structure 118 for up and down travel along the standard.

While the instant invention has been described with reference to a particular embodiment of the invention, it will be readily understood and appreciated that variations and modifications may be made Without departing from the spirit or scope of the invention.

What is claimed is:

1. A sharpener for a cutting edge of a knife blade comprising:

(a) a pair of complementary substantially circular sharpening means having overlapping peripheral portions adapted to receive therebetween the cutting edge of a blade to be sharpened,

(b) each of said sharpening means including,

(c) an arbor means adapted to be mounted on its respective rotary support,

(d) a pair of complementary members connected to said arbor means,

(e) one of said members being fixedly secured to said arbor, and the other member being connected to said arbor means in floating relationship to said fixedly secured member, v

(f) means for resiliently biasing said members for movement away from each other,

(g) means for restraining the force of said biasing means,

(h) one of said members having a laterally extending flange portion defining a substantially true half circle, and said other member having a complementary extending flange defining a segment of a circle which is slightly less than that of a true half circle,

(i) and a true circular abrasive band circumscribing the complementary flange portions of said members to define a true circular abrading surface for engaging with a cutting edge during a sharpening operation, said resilient means maintaining said members biased against the inner circumference of said endless band for detachably securing the same thereto by friction.

2. In combination with a cloth cutting machine having a standard and a straight knife cutter reciprocally mounted on said standard, the improvement comprising:

(a) means adjacent to said cutter to sharpen the cutting edge thereof,

(b) said means including a pair of complementary counter rotating rotary sharpeners adapted to engage with the cutting edge of said knife,

(0) each of said sharpeners including, A

(d) an inner sleeve adapted to receive and rotate on a shaft, said sleeve having a laterally extending flange adjacent one end thereof,

(e) an arbor connected to said sleeve, said arbor having a laterally extending mounting flange,

(f) fastening means detachably secured to one end of said sleeve to secure said arbor in position thereon between the flange of said sleeve and said fastening means,

(g) a pair of complementary shoe members connected to the mounting flange of said sleeve,

(h) each of said complementary shoe members including a peripheral surface portion defined as a segment of a circle,

(i) means for fixedly securing one of said shoe members to said flange of said arbor,

(j) means for moveably mounting said other shoe member on said arbor flange for relative movement toward and away from said fixed shoe member,

(k) said latter means including a pair of apertures formed in said moveable shoe member, and

(l) a pin connected to said arbor extending through said apertures, said apertures having a diameter larger than the diameter of said pins to provide for limited relative movement between said shoe member and said arbor,

(m) resilient spring means disposed between the complementary end portions of said complementary shoe members for biasing said shoe members apart,

(n) and an endless band of abrasive circumscri'bing the complementary peripheral surface portions of the respective shoes whereby said band resists the bias of said spring means,

(0) said rotary sharpeners having the respective abrasive bands circumscribing the same disposed in overlapping relationship.

3. In combination with a cloth cutting machine having a standard and a straight knife cutter reciprocally mounted on said standard, the

improvement of (a) means adjacent said cutter to sharpen the cutting edge thereof,

(b) said means including a pair of complementary rotary sharpeners adapted to engage with the cutting edge of said reciprocating cutter,

(c) means for effecting counter rotation of said corn plementary rotary sharpeners, and

(d) each of said sharpeners including,

(e) an inner sleeve adapted to receive and rotate on a shaft, said sleeve having a laterally extending flange adjacent one end thereof, and

(if) said sleeve being externally threaded at each end portion thereof,

(g) an arbor fitted on the exterior surface of said sleeve, said arbor including a laterally extending mounting flange connected thereto,

(h) a nut threaded to one threaded end of said sleeve to secure said arbor in position thereon between the flange of said sleeve and said nut,

(i) a pair of complementary members connected to said mounting flange of said arbor, each of said members being formed with a complementary groove for accommodating said mounting flange,

(j) one of said members having a laterally extending flanged edge having an external peripheral surface defined as a true half circle of 180",

(k) means for fixedly securing said one member to said mounting flange of said arbor,

(1) and the other of said complementary members having a complementary laterally extending flanged edge having an external peripheral surface defined as a segment of a circle of less than 180,

(m) means for moveably mounting said other memher on said arbor flange for relative movement to Ward and away from said fixed member,

(u) said latter means including a pair of apertures 'formed in said other member,

(0) a pin extending through each of said apertures and said arbor flange, saidapertures having a diameter larger than the diameter of said pins to provide for limited relative movement therebetween,

(p) resilient spring means disposed between the com plementary end portions of said members for bias- 'ing said members apart,

(q) and an endless band of abrasive circumscribing the complementary flanged edge portions of the respective members whereby said band resists the bias of said spring means,

(r) and each of said rotary sharpeners having their respective extending edge portions and abrasive band circumscribing the same disposed in overlapping relationship.

4. The invention as defined in claim 3 wherein one of said rotary sharpeners supports a single band of abrasive and said other rotary sharpener supports a plurality of spaced abrasive bands so of said rotary sharpeners that in the overlapped position abrasives of said other sharpener.

References Cited UNITED STATES PATENTS 1,354,866 10/ 1920 Wolfe 51-353 2,156,798 5/ 1939 Bangser 51-249 2,207,439 7/ 1940 Monjar 51374 2,5 65,286 9/1951 Way 5 l385 X FOREIGN PATENTS 63 1,484 6/ 1936 Germany.

7,911 8/ 1906 Great Britain.

HAROLD D. WHITEHEAD, Primary Examiner.

the single band of abrasive of one sharpener is disposed between the plural bands of 

1. A SHARPENER FOR A CUTTING EDGE OF A KNIFE BLADE COMPRISING: (A) A PAIR OF COMPLEMENTRAY SUBSTANTIALLY CIRCULAR SHARPENING MEANS HAVING OVERLAPPING PERIPHERAL PORTIONS ADAPTED TO RECEIVE THEREBETWEEN THE CUTTING EDGE OF A BLADE TO BE SHARPENED, (B) EACH OF SAID SHARPENING MEANS INCLUDING, (C) AN ARBOR MEANS ADAPTED TO BE MOUNTED ON ITS RESPECTIVE ROTARY SUPPORT, (D) A PAIR OF COMPLEMENTARY MEMBERS CONNECTED TO SAID ARBOR MEANS, (E) ONE OF SAID MEMBERS BEING FIXEDLY SECURED TO SAID ARBOR, AND THE OTHER MEMBER BEING CONNECTED TO SAID ARBOR MEANS IN FLOATING RELATIONSHIP TO SAID FIXEDLY SECURED MEMBER, (F) MEANS FOR RESILIENTLY BIASING SAID MEMBERS FOR MOVEMENT AWAY FROM EACH OTHER, (G) MEANS FOR RESTRAINING THE FACE OF SAID BIASING MEANS, 